MERLIN ROCKET FORUM

Topic : Trying to understand the design evolution route...

I am considering the purchase of a new boat with or without design modifications. To that end I am trying to understand the thought processes behind the general evolution of the hull shape in recent years. What each modification was trying to achieve, which modifications were successful, which not, & under what circumstances. What are peoples observations…

In addition

1)What is the verdict on the new Keith Callager design(s) & have any serious boat on boat evaluations been carried out by anyone?

2)Has anyone tried out an NSM 4 with a modern carbon rig & have any serious boat on boat evaluations been carried out?

3) Where does the "Make it so" design fit into the evolution. What were its perceived strengths & weaknesses. Have any serious boat on boat evaluations been carried out?

4) "Joy Rider" was an Allan Jackson modification of a Canterbury Tails. Has anyone compared the shape & measurements of this with the Winder modifications of the Canterbury Tails. Once again have any serious boat on boat evaluations been carried out?

What are watchers observations? For instance it is quite easy to observe that a boat with a carbon mast pitches less than a boat with an aluminum mast. What are people observations from the balcony at Salcombe?

Thanks in advance.


Posted: 25/11/2009 03:39:38
By: DO
I am not really qualified enough to answer all of your queries, but I would say that there is very little difference in boat speed between most of the hull shapes in the last 12 years or so. Most of the gain is down to the ig and sails and of course the helm and crew.

The Make it so is just as quick as the rest in the right hands. It's major downfall is that Lawrie can't build them cheap enough of fast enough to compete with the winders. Keiths designs are still a little un-tested as of yet. There is a good article in the new Mag by Keith explaining a little about it.

I think it really is going to depend on your situation as to what you buy. If I had garage storage for a boat and enough money to buy a new one I might see if I could get Lawrie Smart to build me a new Make it so 2, or maybe even a Let it Ride. I still thik they are the quickest design out there, just not being built by Kevin anymore (he might though?) otherwise you might like to try his latest incarnation of it, the Ticket To Ride.

Hope that has been some help. I am sure someone more qualified will post some advice too.


Posted: 25/11/2009 08:53:39
By: Jez3645
I can't imagine that Kevin would turn down the opportunity to build a wooden Merlin


Posted: 25/11/2009 09:02:50
By: David
I thought Glen Trystwell's boat was the fastest. He modified an old let it ride with no correctors and put more rocker in the bow ( opposite to the windy principal) means the boat can tack quicker or something and then there is a complicated article about it in the Mag which goes into drag co-efficients and prismatic co-efficients or something.seems the designs is evolving all the time .....or going backwards ????


Posted: 25/11/2009 09:03:44
By: not a naval architect
The advice given to me was: "don't even think about it".
Any design modifications are so small they make very little difference. If they were important, then anyone / everyone would have jumped on them already.
Instead, buy the "standard" (glass Winder or Smart for wood) and sail it. If in the process you end up in the top 10 at the Nationals, then you will know how the boat feels and whether you want to improve it in certain conditions (and you will also know what the negative implications of those improvement are!).
There are also improvements available from the rig (mast and sail): stiffer sideways at the top to carry more weight? better luff curve for lighter winds? more flexible to handle the gusts or lighter weights?

But it is a fascinating subject that seems to have kept the fleet alive for at least 50 years: how to find the edge that no-one else noticed.


Posted: 25/11/2009 09:39:20
By: ChrisJ
The thing that interested me in Glen's article was about immersion tests and checking on the centre of buoyancy and the way this had influenced what he did to the bow sections.  Does anyone know what was done and how?

I sail a boat to a design that never really took off but led to the Let it Ride, which did. What is evident is that the differences in boatspeed are small. I was planing through the bag neck and neck with the new Callaghan design and a couple of Winders. Boathandling and gust spotting made the difference, there was no real difference in boatspeed in steady conditions. Having said that, in a fleet where little separates the top 15 boats at the Champs a very small edge in boatspeed may make the difference between being 1st and 12th at the windward mark and Glenn certainly thought he had that edge. If you talk to Laurie about his designs he makes a big issue of the bow buoyancy and heavy weather handling, the bow sections are quite different in shape and the distortion just before midlength to satisfy the rise of floor point which you can clearly see in the CT isn't there. Glenn's article suggested his modifications made most difference in light to moderate wind strengths. It's all compromise, as if you want low wetted area and quick tacking you still want a Holt boat or a 9B, but of course you lose the downwind speed and stability. What can you gain in condition X without losing speed in condition Y.


Posted: 25/11/2009 09:59:05
By: Andrew M
Here is a formulae for you:

Take - modicum natural talent + (Get fit + don't drink + sail flat) X 1 good crew = Competetive.

Worked for WW


Posted: 25/11/2009 10:28:17
By: ITK
I think Glens article as it appeared in the Magazine, which was more or less a reprint of the one in Yachts and Yachting a month earlier, was one of the best things I have read on sailing in the past few years. Well written clear and logical. However what is clear despite his protestations as an amateur, is that without his trade connections, and perhaps even with, it was a very expensive exercise well beyond anyone who works "without" the trade or who does not have very deep pockets and in either case very little home life! 
Plus of course substantial quantities of raw talent in Helmsman and crew.
It is perhaps the lack of time and the cost of doing something different, with its possible downside, that prompts most people to opt for the safe option.


Posted: 25/11/2009 10:41:25
By: Ancient Geek
ITK have you thought about trying it yourself, other than the missing talent, fitness, alcoholic abstainence and the ability to sail flat you have all the ingredients.........


Posted: 25/11/2009 11:18:15
By: WP
Hi, I may be able to offer some more information with regard to development as I have been involved in some of it and carefully monitored what is currently happening, and Yes Glenn's mods are certainly interesting and present another view of which route gives the advantage. Fore and aft balance is crucial to the dynamics of the boat.
In the mid 1990s the Let it Ride was the fastest shape but could be tricky in breeze. Alan Jackson and I, with my bank account, developed the Joy Rider as an option and if there was a mould would to build in composites, would match any design now being built. When she hit the water, she immediately offered an option to the Let it Ride coming second on her first launching/TT event. Unfortunately Chipstow was not fashionable at the time and so Jacko did not get orders from none east coast/London sailors. The Joy Rider, was the first to have the dropped bow (the Winder Mk4 mod 2 comes very close to the design) which gave the boat more grip upwind in chop and was a trade off for fast tacking but worth it. Also the plate was moved as near to the underside/rear of the mast as possible without changing the internal layout. This brought the CofE above and under the water into alignment and made the boat more responsive (even at 48 in. rake). Aft of the case the boat has near on no rocker and the first two planks are max width to increase offwind top end speed and stability. The trade off was she was slightly more stiff on close reaches but still quick. The Winder has progressively moved towards this design and is now quite close below the water if you were to buy a Mk4 mod2 which is the standard late 2008 onwards supplied boat. If I was taking delivery of my new boat now (still held on order as building a house instead), I'd be taking this shape. Contrary to previuos posts, if racing at the front of the fleet and looking for the edge the shape is very important as is one string and the above water and below water attachments. However, to justify the cost, make sure you and your crew are fit and well versed in the mechanics of the thoroughbred Merlins of today.


Posted: 25/11/2009 12:53:41
By: barnsie
Yes, but I would need a good crew....


Posted: 25/11/2009 14:30:23
By: ITK
Urm, BAU has lead in her, 7 kg according to the certificate. Always had from day one. Having now sailed her , we were immediately in amongst people that were usually on the horizon. Being able to fly the kite in 28 knots whould have helped too, but then Glen rigged it for us so the downhaul was too short, cutting the kite in two and making it unstable.

Anyway, I agree with the sentiments earlier, there is little difference in the shapes now. Keep the waterline as narrow as possible and the rocker aft as flat as possible, consistent with the loaded displacement required. Simples .....

Besides, Glen won with an unconventional sail design & maker, fat foils and an unbroken Chippie stick. He also got more starts right this year, but actually I think that he was probably faster through the water at Looe, just gave Roger too much of a head start up the first beat. Richard having the wobbles helped this year too.

Unless you are happy to be semi-pro about your yachting, spend to the same level as those at the front, then you will not notice the difference between a Mk 1 to 6 Winder. If you love wood (and we do) then get one of the LIR - yes Kevin would build another one, if you can afford it - but you will not get the same shape as BAU, nor other LIR's as each one is different. Linton has the Easy Roller moulds and there was a recent pull off those. Gut feel is that the Hazardous '09 is on the right path and needs more time "out there", but fair play to Rob, Keith and Lawrie for taking a new route.

Budget, crew, time, ability and aspiration are the questions that need answering before you worry about design.


Posted: 25/11/2009 20:01:24
By: Andy Hay - 3626 Business as Usual
Hasn't Glenn pretty much converted a'Let it Ride' into the only ever wood 'Easy Roller' as this added a bit more rocker to the earlier design for all the reasons he described?


Posted: 25/11/2009 20:21:06
By: Geoff Wright
My understanding is that there were two "cuts", well, three if you include Mike's original (photo of this in progress on Linton's web site). Firstly, Mike dropped the nose. Glen and Jo Richards then nipped in the aft sections / transom first then secondly removed some of the original nose drop to give a little more forward rocker. Of course, there are probably a number of tweaks to smooth the water path around the hull.

If anything I'll just fair & paint the hull and smooth out the bilge keels when I turn her over in the spring for her pre-season boat bumbling session. Possibly replace the hoop with a carbon one, titivate the foils and replace and re-run some of the control lines. Then again, might just go out and enjoy Business as Usual as she is!

Kevin did offer to build a woodie over the hull plug for the Easy Roller ...


Posted: 25/11/2009 20:58:08
By: Andy Hay - 3626 Business as Usual
1) Jury is still out on the Hazardous 09. Did well at Salcombe against it's peers but needs to fall into the right hands and have a go against the front of the fleet.

2) There are NSM IVs that have been carbonised. They go well inland as far as i know.

3) The Make it So is a good boat. It didn't achieve popularity because the Winder boat appeared at more or less the same time. Lower mainteneance, cheaper, and better availability won the day.

4) Joyrider had a good champs at Abersoch but again didn't capture the fleets imagination. I don't know if it was measured by Graham Scroggie, i know he did do most designs but 3547 was probably up here in the Midlands by then.

If new to the fleet i think playing the hull shape lottery is a bad idea. Canterbury Tales and Let it Ride are both well proven hulls and a good place to start.


Posted: 26/11/2009 07:32:38
By: Chris M
Hi 3547 and 3579 were the only true Joyriders and primarily built for a short chop, ie sea sailing. They in fact had several very good Champs between them and and if I'd stayed in Merlins full time after Abersoch, would have been in the hunt, but alas other things overtook me and post Abersoch was a cameo of what most people were doing, leaving the class the following year. I took 3579 (having not stepped in a Merlin since 2001) to the last Tenby with knackered sails and reasonable crew (now good both front and back so I understand) and were still at the sharp end but lost out downwind (had dodgy tiny kite (found out when we overlayed it on another sailmaker's kite), but enough about that). If either boat was one stringed and had the right kit and in the right hands, they'd be up there with a chance and I considered commissioning a mould prior to placing a deposit for a Winder. Having also owned one of the last built NSM4s, would say that the design is not slow but against the modified Tales are outclassed. Inland on flat water, I cannot comment as did not spend enough time puddle sailing prior to selling the NSM4.  
Hope that is of help.


Posted: 26/11/2009 10:27:08
By: barnsie
So one or two NSM 4's have modern carbon rigs. Does anyone know which ones?


Posted: 26/11/2009 13:16:46
By: DO
NSM2&4 are not as quick planing as CT and derivatives.  It's possible the 4 is a bit better but in carbon rigged NSM2 I remember a race at Chichester rounding one mark right up Hywel's transom (he had probably tacked straight in front of me as usual) and ending a long close reach over 100 yds behind.  The boat was well set up with pretty good sails and it was simply a boat speed issue.  After losing a race to the line in a similar way at Salcombe the same year I moved the rig to Heaven Sent and it was no longer a problem.


Posted: 26/11/2009 13:42:44
By: Andrew M
If you have a healthy budget, happy to be radical in your approach and buck the trend, as Rob Holroyd has bravely done, then take the plunge, give Laurie Smart a call and get either a 'Make it So' Mk2 or Hazardous - Zero built. Both absolutely cracking boats and very fast in the right hands. And don't be put off by wood. It is actually a lot, lot easier to work with, adapt and repair as opposed to the plastic jobbies.

http://www.bluelightning.co.uk/Merlins/hazardous.htm

Posted: 26/11/2009 16:01:23
By: Richard Battey
or at a base cost of £999,  say £1k, shell only, build one yourself or buy the kit and get Laurie or a.n.other to assemble it professionally! The subject of free issue kits has been touched on before, just need to add the labour cost, fittings spars, sails etc,etc.


Posted: 26/11/2009 16:05:32
By: Richard Battey
If you are looking second hand, again dependant on budget I would look at 3640 Simon Blakes Make it So 2, 3543 Chris Martins Let it Ride or 3411 Ian Suttons NSM4. All three are good boats at good prices with carbon and all the bits. 3 very different budgets though.


Posted: 26/11/2009 16:07:57
By: Jez3645
3389 White Whale is worth a look at too also an NSM4 and a proven race winner in its day.

What type of sailing are you looking at doing? WHere are you going to be doing it?


Posted: 26/11/2009 16:11:07
By: Jez3645
Richard, you were quick off the mark to point out the actual availability of a Merlin kit (rather than my hitherto hypothetical mumblings) - I updated my website only yesterday. I have purchased a kit (not to build myself, but for resale) and it is now sitting in my back garden ready to unpack tomorrow. I will take some photos and post them on my website. You clearly see the potential of this route - let's hope there will be some takers.

http://www.bluelightning.co.uk/Merlins/hazardous.htm

Posted: 26/11/2009 20:55:39
By: Keith Callaghan

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